From patchwork Mon Oct 12 13:26:24 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 270387 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 88771C43467 for ; Mon, 12 Oct 2020 13:34:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 51B052074F for ; Mon, 12 Oct 2020 13:34:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1602509669; bh=mf2qh4WZVg4my0bCzetvDhzrQB7CqPMDZIobCTaGKyo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=xWypHG/D3v79TkZu7N8TqAVCI+gJIUIDt8S9TZbafAuWz9xTIUjnT8KWodjjbIDNf fQDfX85rogOyDU/TidntXVRqDEJ1LnXNw5kzVfno3lgDT/HGsr0CBu61ok7qWPhkEm uECgt8Y9DqE94CTx52lhx31/Mf7imy6G2VAMqLN8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730645AbgJLNe2 (ORCPT ); Mon, 12 Oct 2020 09:34:28 -0400 Received: from mail.kernel.org ([198.145.29.99]:36756 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729297AbgJLNeX (ORCPT ); Mon, 12 Oct 2020 09:34:23 -0400 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 6938221D7F; Mon, 12 Oct 2020 13:33:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1602509623; bh=mf2qh4WZVg4my0bCzetvDhzrQB7CqPMDZIobCTaGKyo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iLZ690hde+Ju7bQRUR4RHmy7tN3ZzF/MlyAOCuz2xPFcdZqCduWQBBnFSiehP8DXh 7fA5vzFVH2Rrt1t3hM88SB4NJwA1x+FMD8lCMiRkJLUseZiPx+X+rckzbgNI8Li8dx uB01gbnzk4eeSLQ8OK/XtUpd6NbUy5n2xJC/wgrg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Stefan Hajnoczi , "Michael S. Tsirkin" , Stefano Garzarella , "David S. Miller" , Sasha Levin Subject: [PATCH 4.9 02/54] vsock/virtio: stop workers during the .remove() Date: Mon, 12 Oct 2020 15:26:24 +0200 Message-Id: <20201012132629.711227488@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20201012132629.585664421@linuxfoundation.org> References: <20201012132629.585664421@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Stefano Garzarella [ Upstream commit 17dd1367389cfe7f150790c83247b68e0c19d106 ] Before to call vdev->config->reset(vdev) we need to be sure that no one is accessing the device, for this reason, we add new variables in the struct virtio_vsock to stop the workers during the .remove(). This patch also add few comments before vdev->config->reset(vdev) and vdev->config->del_vqs(vdev). Suggested-by: Stefan Hajnoczi Suggested-by: Michael S. Tsirkin Signed-off-by: Stefano Garzarella Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- net/vmw_vsock/virtio_transport.c | 46 +++++++++++++++++++++++++++++++- 1 file changed, 45 insertions(+), 1 deletion(-) diff --git a/net/vmw_vsock/virtio_transport.c b/net/vmw_vsock/virtio_transport.c index 32ad7cfa5fa74..67aba63b5c96d 100644 --- a/net/vmw_vsock/virtio_transport.c +++ b/net/vmw_vsock/virtio_transport.c @@ -39,6 +39,7 @@ struct virtio_vsock { * must be accessed with tx_lock held. */ struct mutex tx_lock; + bool tx_run; struct work_struct send_pkt_work; spinlock_t send_pkt_list_lock; @@ -50,6 +51,7 @@ struct virtio_vsock { * must be accessed with rx_lock held. */ struct mutex rx_lock; + bool rx_run; int rx_buf_nr; int rx_buf_max_nr; @@ -57,6 +59,7 @@ struct virtio_vsock { * vqs[VSOCK_VQ_EVENT] must be accessed with event_lock held. */ struct mutex event_lock; + bool event_run; struct virtio_vsock_event event_list[8]; u32 guest_cid; @@ -91,6 +94,9 @@ virtio_transport_send_pkt_work(struct work_struct *work) mutex_lock(&vsock->tx_lock); + if (!vsock->tx_run) + goto out; + vq = vsock->vqs[VSOCK_VQ_TX]; for (;;) { @@ -147,6 +153,7 @@ virtio_transport_send_pkt_work(struct work_struct *work) if (added) virtqueue_kick(vq); +out: mutex_unlock(&vsock->tx_lock); if (restart_rx) @@ -230,6 +237,10 @@ static void virtio_transport_tx_work(struct work_struct *work) vq = vsock->vqs[VSOCK_VQ_TX]; mutex_lock(&vsock->tx_lock); + + if (!vsock->tx_run) + goto out; + do { struct virtio_vsock_pkt *pkt; unsigned int len; @@ -240,6 +251,8 @@ static void virtio_transport_tx_work(struct work_struct *work) added = true; } } while (!virtqueue_enable_cb(vq)); + +out: mutex_unlock(&vsock->tx_lock); if (added) @@ -268,6 +281,9 @@ static void virtio_transport_rx_work(struct work_struct *work) mutex_lock(&vsock->rx_lock); + if (!vsock->rx_run) + goto out; + do { virtqueue_disable_cb(vq); for (;;) { @@ -376,6 +392,9 @@ static void virtio_transport_event_work(struct work_struct *work) mutex_lock(&vsock->event_lock); + if (!vsock->event_run) + goto out; + do { struct virtio_vsock_event *event; unsigned int len; @@ -390,7 +409,7 @@ static void virtio_transport_event_work(struct work_struct *work) } while (!virtqueue_enable_cb(vq)); virtqueue_kick(vsock->vqs[VSOCK_VQ_EVENT]); - +out: mutex_unlock(&vsock->event_lock); } @@ -521,12 +540,18 @@ static int virtio_vsock_probe(struct virtio_device *vdev) INIT_WORK(&vsock->event_work, virtio_transport_event_work); INIT_WORK(&vsock->send_pkt_work, virtio_transport_send_pkt_work); + mutex_lock(&vsock->tx_lock); + vsock->tx_run = true; + mutex_unlock(&vsock->tx_lock); + mutex_lock(&vsock->rx_lock); virtio_vsock_rx_fill(vsock); + vsock->rx_run = true; mutex_unlock(&vsock->rx_lock); mutex_lock(&vsock->event_lock); virtio_vsock_event_fill(vsock); + vsock->event_run = true; mutex_unlock(&vsock->event_lock); vdev->priv = vsock; @@ -560,6 +585,24 @@ static void virtio_vsock_remove(struct virtio_device *vdev) /* Reset all connected sockets when the device disappear */ vsock_for_each_connected_socket(virtio_vsock_reset_sock); + /* Stop all work handlers to make sure no one is accessing the device, + * so we can safely call vdev->config->reset(). + */ + mutex_lock(&vsock->rx_lock); + vsock->rx_run = false; + mutex_unlock(&vsock->rx_lock); + + mutex_lock(&vsock->tx_lock); + vsock->tx_run = false; + mutex_unlock(&vsock->tx_lock); + + mutex_lock(&vsock->event_lock); + vsock->event_run = false; + mutex_unlock(&vsock->event_lock); + + /* Flush all device writes and interrupts, device will not use any + * more buffers. + */ vdev->config->reset(vdev); mutex_lock(&vsock->rx_lock); @@ -581,6 +624,7 @@ static void virtio_vsock_remove(struct virtio_device *vdev) } spin_unlock_bh(&vsock->send_pkt_list_lock); + /* Delete virtqueues and flush outstanding callbacks if any */ vdev->config->del_vqs(vdev); mutex_unlock(&the_virtio_vsock_mutex);